Magnetic ink character recognition apparatus and magnetic ink character recognition method

ABSTRACT

Column misalignment between a magnetically-recognized character string and an optically-recognized character string is corrected to improve character recognition reliability. A character string is read magnetically and the result outputted. The same character string is also read optically and the result outputted. A magnetic data reading unit detects the magnetism of a character string printed in magnetic ink and outputs the detected magnetic data. A recognition result comparing unit then applies a column offset detection process to detect misalignment between the character columns in the magnetic and optical results, then applies a column offset correction process to correct any column offset and align corresponding character columns. The comparing unit then compares corresponding character columns in the magnetic data recognition result and image data recognition result. For each position comparison, the comparing unit outputs the common character if the magnetically-recognized and optically-recognized character at that position match, or a question mark if the magnetically-recognized and optically-recognized character at the position do not match or if one or both of the magnetically-recognized or optically-recognized character is missing.

CONTINUING APPLICATION DATA

This application is a continuation of, and claims priority under 35U.S.C. §120 on, U.S. application Ser. No. 11/253,403, filed Oct. 19,2005, the content of which is incorporated by reference herein in itsentirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to technology for recognizing charactersprinted in magnetic ink on the surface of a check.

2. Description of the Related Art

Check processing devices that have a magnetic ink character reader(MICR) for reading magnetic information denoting characters printed withmagnetic ink on the surface of a check, and for recognizing the magneticink characters from this magnetic information are now common. Some checkprocessing devices also use an optical character reader (OCR) to improvecharacter recognition accuracy by additionally optically reading andrecognizing the characters. These check-processing devices combine themagnetic data recognition result and the optical data recognition resultto improve the reliability of the character recognition process. See,for example, Japanese Unexamined Patent Application 2000-344428.

However, combining the magnetic data recognition result and optical datarecognition result does not improve character recognition reliabilityunder certain circumstances. If, for example, reliability is improved bycomparing the magnetic data recognition result and optical datarecognition result character by character, a mismatch will be confirmedbetween substantially all of the characters if a shift of just a singlecharacter column occurs between the optical and magnetic datarecognition results.

SUMMARY OF THE INVENTION

The present invention solves this problem and improves characterrecognition reliability by correcting such shifts in the charactercolumn alignment.

According to one aspect of the present invention, a characterrecognition apparatus that is able to recognize a character stringcomposed of a plurality of characters printed with magnetic ink on aprint medium is provided. This character recognition apparatus generallycomprises: a magnetic sensor for detecting magnetism from the characterstring printed in magnetic ink and outputting magnetic data; an opticalsensor for optically reading the same character string printed inmagnetic ink and outputting image data; magnetic recognition means forrecognizing characters in the character string using the magnetic dataoutput by the magnetic sensor, and outputting a magnetically-recognizedcharacter string; image recognition means for recognizing characters inthe character string using the image data output by the optical sensor,and outputting an optically-recognized character string; column offsetdetection means for detecting a shift in column alignment of charactersin the magnetically-recognized character string with respect tocorresponding characters in the optically-recognized character string;column offset correction means for correcting the column offset andaligning corresponding character corresponding characters in themagnetically-recognized and optically recognized character strings, ifand when the column offset detection means detects a shift in charactercolumn alignment; and comparison means for comparing results atcorresponding positions in the magnetically-recognized andoptically-recognized character strings based on the column alignmentafter column offset correction is performed by the column offsetcorrection means, and, for each position comparison, outputting (1) thecommon character if the magnetically-recognized and optically-recognizedcharacter at that position match, or (2) a question mark ifmagnetically-recognized and optically-recognized character at thatposition do not match or if one or both of the magnetically-recognizedor optically-recognized character is missing. The final output is then astring of characters or characters and one or more question marks.

The column offset detection means preferably determines that there is anoffset in the character column alignment when the number of charactersin the magnetically-recognized character string and the number ofcharacters in the optically-recognized character string are not thesame; and the column offset correction means corrects the column offsetby shifting one of the magnetically-recognized character string or theoptically-recognized character string relative to the other by an amountequal to or less than the difference in the number of characters in thestrings.

Further preferably: the magnetic sensor outputs with the magnetic datamagnetic position information denoting the position where magnetism of aparticular character was detected; the image recognition means detectsthe position of each character during character recognition, and outputsimage position information denoting the corresponding detectedpositions; the column offset detection means thus detects a columnoffset by comparing the position of the first or last character of themagnetically-recognized character string based on the magnetic positioninformation and the position of the corresponding first or lastcharacter of the optically-recognized character string based on theimage position information.

In one embodiment, the column offset correction means alignscorresponding columns in the character strings based on positioninformation contained in the magnetic position information for eachcharacter in the magnetically-recognized character string and positioninformation contained in the image position information for eachcharacter in the optically-recognized character string.

In another embodiment, the column offset correction means shifts thecorrelation between the magnetically-recognized character string and theoptically-recognized character string based on a first pattern selectedfrom one or more predefined offset patterns to correct the columnalignment.

Further preferably, the column offset correction means selects a secondpattern to correct the column offset, when the match rate of thecharacter strings compared by the comparison means is less than or equalto a specified rate, after correcting the column alignment according tothe selected first pattern.

In another aspect, the invention involves a character recognition methodfor recognizing a character string comprising a plurality of charactersprinted with magnetic ink on a print medium. Such a method generallycomprises: detecting magnetism from the character string printed inmagnetic ink and outputting magnetic data; optically reading thecharacter string printed in magnetic ink and outputting image data;recognizing characters in the character string using the outputtedmagnetic data, and outputting a magnetically-recognized characterstring; recognizing characters in the character string using theoutputted image data, and outputting an optically-recognized characterstring; detecting a shift in column alignment of the characters in themagnetically-recognized character string with respect to correspondingcharacters in the optically-recognized character string; correcting thecolumn offset and aligning corresponding character columns of themagnetically-recognized and optically-recognized character strings, if ashift in the character column alignment is detected; and comparingcharacters at corresponding positions in the magnetically-recognized andoptically recognized character strings based on the column alignmentafter column offset is corrected, and outputting, for each positioncomparison, (1) the common character if the magnetically-recognized andoptically-recognized character at that position match, or (2) a questionmark if magnetically-recognized and optically-recognized character atthat position do not match or if one or both of themagnetically-recognized or optically-recognized character is missing.The final output is then a string of characters or characters and one ormore question marks.

In accordance with further aspects of the invention, the methoddescribed above or steps thereof may be embodied in a set ofinstructions, which is carried on a tangible medium and conveyed to acomputer or other processor-controlled device for execution. The set ofinstructions may be conveniently implemented in software. Alternatively,any or all of the instructions may be implemented using functionallyequivalent hardware (e.g., application specific integrated circuit(ASIC), digital signal processing circuitry, etc.) or a combination ofsoftware and hardware.

Other objects and attainments together with a fuller understanding ofthe invention will become apparent and appreciated by referring to thefollowing description and claims taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a check processing apparatus accordingto a preferred embodiment of the present invention;

FIG. 2 is a plan view of a typical check;

FIG. 3 is a schematic diagram of the transportation path in ahybrid-processing device containing the function of a check processingapparatus;

FIG. 4 is a control block diagram of the check processing apparatus;

FIG. 5 is a function block diagram of the character recognition processin the hybrid processing device; and

FIG. 6 is a schematic diagram of the character recognition process.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment of a check processing apparatus 10 according tothe present invention is described below with reference to theaccompanying figures. As shown in FIG. 1, a check processing apparatus10 according to this embodiment of the invention is composed of a hybridprocessing device 1 for scanning and printing checks C, and a hostcomputer 50 for generating verification data and controlling the hybridprocessing device 1.

The host computer 50 is composed of a keyboard 51 and mouse 52 for dataentry, and a display 53 for displaying an image of the scanned check C,error messages, and other information. The host computer 50 is incommunication with the hybrid processing device 1 by a wired or wirelessconnection. Note that a wired connection using a connector cable isshown in FIG. 1.

The host computer 50 is connected over a network (such as the Internet)to a transaction processing server, which verifies the validity of thechecks C. The host computer 50 receives check data read by the MICR 13part of the hybrid processing device 1 (see FIG. 4) and sends the checkdata to the transaction processing server. Whether check C is valid orinvalid is known based on the response from the transaction processingserver.

Checks C processed by the hybrid processing device 1 according to thisembodiment of the invention and the transaction process that is run toprocess transactions using the checks are described next with referenceto FIG. 2.

As shown in FIG. 2A, a serial number 91, account holder name 92, andmagnetic ink data 98 are preprinted on the front of check C. The frontof check C also has a date line 93, payee line 94, payment amount lines95 and 96, and a signature line 97. The magnetic ink data 98 generallyincludes the bank number, account number, and check serial number. Theinformation printed in the magnetic ink data 98 is read by the MICR 13(see FIG. 4) to verify the validity of check C.

The user (account holder) writes or prints the date, payee, and paymentamount in the appropriate places on the front of check C, then signs thecheck in the signature line 97, and passes the check to the payee (astore in this example).

The store then prints an endorsement including deposit informationproving that check C was accepted by the store in an endorsement area onthe back of check C. The store then sends check C to the bank A that isused by the store, and the bank A processes check C. Referring to FIG.2B, note that the back of check C has an endorsement area C1 that isused by the store to endorse check C, and a spray-on area C2 where thebank or clearinghouse prints check verification and clearing data. Thestore records the endorsement in the endorsement area C1.

After printing the payment amount in magnetic ink characters on thefront of check C, the bank reads the magnetic ink data 98 preprinted oncheck C using the MICR 13, confirms the check validity, and prints theverification data d indicating that check C has been processed by thebank in the spray-on area C2 on the back of check C. The bank also scansthe front and back of check C and stores the image data. Note that thecontent of the verification data d may vary according to the bank, buttypically includes at least the bank name, bank number, the date thecheck was processed, and a tracking number.

The bank then transfers the payment (check) amount from the user'schecking account to the account of the store where check C was used forpayment. If the bank used by the user and the bank used by the store aredifferent, check C data, specifically the payment amount and checknumber, are sent to the bank on which check C is drawn for transactionprocessing.

The arrangement of the hybrid processing device 1 is described next. Asshown in FIG. 1 the hybrid processing device 1 has a U-shapedtransportation path P. Disposed facing the transportation path P are animage reading unit 100 (see FIG. 3) for optically imaging check C, amagnetic data reading unit 110 for magnetically reading the magnetic inkcharacters printed on check C (see FIG. 3), and a printing unit 120 forprinting the verification data on check C. A transportation mechanism 20for conveying checks C through the transportation path P is alsoprovided (see FIG. 3).

As shown in FIG. 3 the transportation path P is composed of a slit-likepath rendered between an outside guide 2 a and an inside guide 2 b, andhas straight portions 35 a and 35 b, and a U-shaped bottom portion 34communicating straight portion 35 a on one end thereof with straightportion 35 b on the other end.

When the user inserts a check C from the check insertion slot 3 to thetransportation path P, the transportation mechanism 20 conveys check Cin the direction of arrow A through straight portion 35 a to theU-shaped bottom portion 34, and thus changes the direction of checktravel 180 degrees from the insertion direction indicated by arrow A.The transportation mechanism 20 then conveys check C through straightportion 35 b in the direction of arrow B, and discharges check C fromthe check exit 4. The transportation mechanism 20 thus curves andconveys check C in the shape of a U through the transportation path P.Note that operation of this hybrid processing device 1 assumes thatcheck C is inserted with the front of the check facing the inside guide2 b.

The transportation mechanism 20 has first transportation rollers 6,second transportation rollers 7, and discharge rollers 8. These rollerpairs 6, 7, 8 each include a drive roller 6 a, 7 a, 8 a driven by amotor, and a grip roller, which is a pressure roller (driven roller) 6b, 7 b, 8 b that presses check C against the opposing drive roller.

The first transportation rollers 6 are disposed at a first cornerportion of the transportation path P. A BOF (bottom of form) detector 9is disposed on the upstream side of the first transportation rollers 6,and a TOF (top of form) detector 16 is disposed on the downstream sideof the first transportation rollers 6. These detectors 9, 16 detect theleading and trailing ends of check C traveling through thetransportation path P. When the BOF detector 9 detects a check C, amotor 40 is driven and the first transportation rollers 6, secondtransportation rollers 7, and discharge rollers 8 start turning.

A back image scanner 11 and front image scanner 12 of the image readingunit 100, and the MICR 13 of the magnetic data reading unit 110, aredisposed to the U-shaped bottom portion 34 between the TOF detector 16and second transportation rollers 7.

These two scanners 11, 12 have image scanning sensors for capturingimages of the back and front of the check. The back image scanner 11 isdisposed on the outside guide 2 a side of the transportation path P forimaging the back side of check C, and the front image scanner 12 isdisposed on the inside guide 2 b side of the transportation path P forimaging the front side of check C. A pressure member (roller) 11 a, 12 adisposed on the opposite side of the transportation path P as thecorresponding scanner 11, 12 presses check C to the scanning surface forscanning.

The MICR 13 is a magnetic reading sensor for reading the magnetic inkcharacters printed on the front of check C, and is disposed on theinside guide 2 b side of the transportation path P at an appropriateposition opposite the front of check C. A pressure member (pad) 13 adisposed on the opposite side of the transportation path P as the MICR13 presses check C to the MICR 13 for reading the magnetic inkcharacters.

The second transportation rollers 7 are disposed to the second cornerportion of the transportation path P, and the discharge rollers 8 aredisposed near the check exit 4. A print head 14 constituting theprinting unit 120 is disposed facing the transportation path P in thestraight portion 35 b between the second transportation rollers 7 anddischarge rollers 8. This print head 14 is mounted on a carriage 15,which is disposed movably along a guide shaft 15 a, and can thus move onthe carriage 15 between a printing range 18 and a retracted position 19.

To print on a check C, the print head 14 stops at a specific position inthe printing range 18 and is driven synchronized to check Ctransportation. As described in further detail below, if roll paper isintroduced to 35 b, roll paper transportation in a subscanning directionand print head 14 movement in a main scanning direction are coordinatedto print the roll paper.

The discharge rollers 8 and check exit 4 are located downstream from theprint head 14. The printed check C is discharged by the dischargerollers 8 from the check exit 4. A discharge detector not shown is alsodisposed near the discharge rollers 8 for detecting whether the printedcheck C has been discharged.

Note that in this embodiment of the invention the height of the outsideguide 2 a and inside guide 2 b is lower than the height of check C inthe parts of the transportation path P other than the U-shaped bottomportion 34 where the scanners 11, 12 and MICR 13 are disposed so thatcheck C can be easily removed if a paper jam occurs, for example.

In addition to the transportation path P for conveying checks C asdescribed above, the hybrid processing device 1 of the present inventionalso has a roll paper transportation path (not shown) for conveying rollpaper. This roll paper transportation path shares part of straightportion 35 b of the transportation path P and conveys the roll paper atsubstantially a right angle to the transportation direction of thetransportation path P (that is, in the direction passing through thesurface of the paper in FIG. 3). A roll paper compartment for storingthe roll paper is also disposed between the straight portions 35 a and35 b of the transportation path P. One end of the transportation path ispulled from this roll paper compartment into the roll papertransportation path and thus conveyed through the roll papertransportation path. When the roll paper passes through the printingrange 18 proximally opposite the print head 14, the print head 14 movesin a main scanning direction to print on the roll paper.

A hybrid processing device 1 according to this embodiment of theinvention can thus both process checks C and issue receipts by printingto roll paper.

The hybrid processing device 1 according to this embodiment of theinvention also has a vertical transportation path rendered appropriatelyto the print head 14 when the print head 14 is positioned in theprinting range 18. This vertical transportation path conveys a checkvertically passed the print head 14 when a check C is inserted betweenthe outside guide 2 a and inside guide 2 b from a top opening formedbetween the outside guide 2 a and inside guide 2 b near the printingrange 18. This vertical transportation path is used for validationprinting whereby a check C inserted from above the transportation path Pis printed by the print head 14 and then discharged again to the topafter printing is completed.

The print head 14 in this embodiment of the invention is mounted on acarriage 15 and can thus move horizontally through the printing range 18along the straight portion 35 b of the transportation path P. Thishybrid processing device 1 thus has two printing modes for printingchecks C, a stationary print head mode in which the print head 14remains stationary while check C moves horizontally passed check Cduring printing, and a stationary check mode in which check C remainsstationary while the print head 14 moves horizontally over the surfaceof check C while printing.

When printing roll paper the print head 14 prints one line at a timewhile moving on the carriage 15 horizontally over the roll papersurface. When multiple lines are printed, the roll paper is advanced oneline in the subscanning direction after the first line is printed, theprint head 14 then moves horizontally in the main scanning direction toprint the second line, and this operation repeats to print eachsubsequent line.

Check C scanning, magnetic ink character reading, and check printingprocesses are described next. When the user inserts a check C in thedirection of arrow A from the check insertion slot 3, check C isconveyed at a constant speed through the transportation path P.

The BOF detector 9 detects the leading end of check C when check Creaches the BOF detector 9. The detection signal from the BOF detector 9causes the motor 40 to start as described above, and the drive roller 6a of the first transportation rollers 6 thus starts turning. Check C isthus passed to the first transportation rollers 6 and gripped smoothlybetween the drive roller 6 a and pressure roller 6 b. As a result, checkC is conveyed without slipping by rotation of the drive roller 6 athrough the transportation path P along the outside guide 2 a wall ofthe U-shaped bottom portion 34.

When the leading end of check C conveyed by the first transportationrollers 6 reaches the TOF detector 16, the scanners 11, 12 and MICR 13disposed downstream therefrom turn on and enter a standby mode waitingfor check detection. The hybrid processing device 1 according to thisembodiment of the invention thus supplies power to the rollers and otheractive elements only when needed, thus saving power and preventingunnecessary power consumption.

As check C continues traveling forward, the back image scanner 11disposed on the outside guide 2 a side images the back side of check C,and the front image scanner 12 disposed on the inside guide 2 b side ofthe transportation path P images the front side of check C. The MICR 13disposed on the inside guide 2 b side also reads the magnetic data fromthe magnetic ink characters preprinted on check C. As described ingreater detail below, the front image data g1 and back image data g2captured from check C is temporarily stored in the check-front imagedata block 242 and check-back image data block 243 of the checkprocessing apparatus (hybrid processing device) 1, respectively, and theCPU 220 runs specific processes on this data, including a process togenerate merged image data g3.

After check C passes the TOF detector 16 and the leading end thereofreaches the second transportation rollers 7, check C is nipped betweenthe drive roller 7 a and pressure roller 7 b and conveyed by rotation ofthe drive roller 7 a to the straight portion 35 b of the transportationpath.

When check C reaches the printing range 18 proximally opposite the printhead 14, the print head 14 is driven to print check C. The print head 14is stopped at a predetermined position in the printing range 18 at thistime and is driven synchronized to movement of the print medium, thatis, check C, in the main scanning direction to print.

After the back of check C is thus printed by the print head 14, check Cis discharged by the discharge rollers 8 in the direction of arrow B.More specifically, check C is nipped between the drive roller 8 a andpressure roller 8 b so that rotation of the drive roller 8 a conveyscheck C out from the hybrid processing device 1, thus completingprocessing of check C.

The control arrangement of the check processing apparatus 10 composed ofthe hybrid processing device 1 and host computer 50 is described nextwith reference to FIG. 4.

This hybrid processing device 1 is composed of an image reading unit 100for imaging check C, a magnetic data reading unit 110 for reading themagnetic ink characters printed on check C, a printing unit 120 forprinting the back of a check C, a detection unit 130 for detecting theleading end and trailing end of check C, a drive unit 140 for drivingthe transportation mechanism 20 and motor 40, and a control unit 200providing overall control of the hybrid processing device 1.

The image reading unit 100 is composed of the back image scanner 11 andfront image scanner 12, and thus images the back and front of check C.

The magnetic data reading unit 110 is composed of MICR 13 that reads themagnetic ink characters printed on check C.

The printing unit 120 is composed of print head 14, and prints theauthentication data received from the host computer 50 on the back ofcheck C.

The detection unit 130 is composed of BOF detector 9 and TOF detector16, and thereby detects the leading end and trailing end of check C.

The drive unit 140 is composed of the transportation mechanism 20including first transportation rollers 6, second transportation rollers7, and discharge rollers 8, and a motor 40 for rotationally driving thedrive roller 6 a, 7 a, 8 a portion of the plural transportation rollersets 6, 7, 8, and thus controls check C transportation.

The control unit 200 is composed of CPU 220, ROM 230, RAM 240, andinput/output controller (IOC) 210 interconnected over internal bus 250.

ROM 230 has a control program block 231 for storing a program forcontrolling reading and printing check C, generating merged image datag3 by merging the back image data g2 and verification data d receivedfrom host computer 50, and other programs run by the CPU 220, and acontrol data block 232 for storing tables and control data forgenerating merged image data g3.

In addition to working area block 241 used for flags, for example, RAM240 has a check-front image data block 242 for storing the front imagedata g1 captured from check C, check-back image data block 243 forstoring back image data g2 captured from check C, magnetic data block244 for storing the magnetic data read from check C, authentication datablock 245 for temporarily storing the verification data d received fromhost computer 50, and merged image data block 246 for temporarilystoring merged image data g3 produced by merging back image data g2 andverification data d. RAM 240 is thus used as working memory by thecontrol processes.

Logic circuits composed of gate arrays and custom IC devices, forexample, for complementing the functions of CPU 220 and handlinginterface signals exchanged with peripheral devices are incorporatedinto input/output controller 210. The input/output controller 210 canthus directly pass or process and then pass image data captured by thescanners 11, 12, magnetic data read by MICR 13, and verification dataand control data from the host computer 50 to the internal bus 250. Inconjunction with the CPU 220, input/output controller 210 also processesand outputs or directly outputs data and control signals output from theCPU 220 to the internal bus 250 to the printing unit 120.

CPU 220 thus controls the flow of signals and data in the hybridprocessing device 1 by means of input/output controller 210 according toa control program stored in ROM 230 to run the merged image data g3generating process and check C printing process.

The host computer 50, which is in communication with hybrid processingdevice 1, has memory 54 such as ROM or RAM, a CPU 55 for controllinginternal operation of the host computer 50, and driver 56, which is aprogram for controlling the hybrid processing device 1.

Memory 54 stores a control program run by the CPU 55 as well as thecontrol data and tables used by the program in ROM. Memory 54 alsoincludes RAM used as working memory and storage registers, as well asstorage areas for information (such as the bank name and bank number)entered by the operator, and the merged image data g3 and front imagedata g1 for check C received from the hybrid processing device 1, and isused as working memory for the control processes.

When a verification data request command requesting transmission of theverification data is received from the hybrid processing device 1, hostcomputer 50 generates the verification data d by adding the processingdate and a process (tracking) number to the information (bank name andbank number in this example) stored in RAM, and sends the resultingverification data d to the hybrid processing device 1.

The process whereby the hybrid processing device 1 combines thecharacter recognition result from the image data and the characterrecognition result from the magnetic data, and improves the reliabilityof magnetic ink data 98 recognition is described next below. Note thatthe arrangement and function described below are achieved by the CPU 220reading and running a control program from ROM 230.

FIG. 5 is a functional block diagram of the character recognitionprocess of the hybrid processing device 1. As described above, the frontimage data g1 and magnetic data read from check C by image reading unit100 and magnetic data reading unit 110 are stored in check-front imagedata block 242 and magnetic data block 244 in RAM 240, respectively.Note that the magnetic data used herein includes coordinates denotingthe positions where the magnetism of the magnetic ink data 98 isdetected.

An image data recognition unit 310 rendered by the CPU 220 gets frontimage data g1 from RAM 240, analyzes the image to recognize the magneticink data 98, and identifies the location where the magnetic ink data 98was detected.

A magnetic data recognition unit 320 likewise rendered by the CPU 220gets the magnetic data from RAM 240, analyzes the magnetic data torecognize the magnetic ink data 98, and identifies the location wherethe magnetic ink data 98 was detected.

The character location or position refers to a position on the y-axis asshown in FIG. 2A, for example. Note, further, that identifying thecharacter position by the image data recognition unit 310 and magneticdata recognition unit 320 is not essential, and can be omitted by one orboth units.

A recognition result comparing unit 330 implemented by the CPU 220 thencompares the image data recognition result 315 (the character stringrecognized from the image data) output by the image data recognitionunit 310 with the magnetic data recognition result 325 (the characterstring recognized from the magnetic data) from the magnetic datarecognition unit 320, and outputs the result of this comparison ascombined recognition result 335. The combined recognition result 335merges the image data and magnetic data recognition results.

FIG. 6 schematically describes the process executed by the functionalblocks shown in FIG. 5. In the example shown in FIG. 6 the magnetic inkdata 98 is printed in a single line on the front of check C. Themagnetic ink data 98 is read by the image reading unit 100 and magneticdata reading unit 110 with a stain or other foreign matter denoted by atriangle in FIG. 6 hiding a portion of the “1” shown as the firstcharacter in the magnetic ink data 98.

The image data recognition unit 310 extracts an image of the magneticink data 98 from front image data g1, for example, and recognizes thecharacters by pattern matching with character pattern data stored inmemory. The image data recognition unit 310 then outputs the recognizedcharacter string as image data recognition result 315. In this examplethe image reading unit 100 cannot accurately read the first “1.” Thefirst “1” is therefore not recognized, and the string “234999A145” isoutput as image data recognition result 315. Position informationdenoting the location of the character string could also be added toimage data recognition result 315. This position information coulddenote the location of the first or last character in the string, or theposition of each individual character in the string.

The magnetic data recognition unit 320 recognizes the individualcharacters based on the magnetic data, and outputs the resultingcharacter string as magnetic data recognition result 325. The first “1”is correctly recognized from the magnetic data because soiling does notobscure the magnetic signal. However, the “9” in the eighth column isincorrectly recognized as an “8” in the example shown in FIG. 6. Thestring “12349998A145” is therefore output as magnetic data recognitionresult 325. Note that, as with the image data recognition result 315,position information denoting the location of the first, last, or everycharacter in the string could be added to the magnetic data recognitionresult 325.

The recognition result comparing unit 330 compares the character stringof the image data recognition result 315 with the character string ofthe magnetic data recognition result 325 character by character, andoutputs the character string of the combined recognition result 335.Operation of the recognition result comparing unit 330 includes aprocess for detecting a shift in the character columns of the characterstring in the image data recognition result 315 and the character stringin the magnetic data recognition result 325, a process for correctingthe detected column shifting (misalignment), and a process for comparingthe character string of the image data recognition result 315 and thecharacter string of the magnetic data recognition result 325 after thecharacter columns are correctly aligned.

The column shifting detection process is described first below. Therecognition result comparing unit 330 could compare the number ofcharacters (columns) in the character string of the image datarecognition result 315 with the number of characters in the characterstring of the magnetic data recognition result 325, and determine thatthe character columns of the two strings are offset from each other ifthe character counts are not the same. Alternatively, the recognitionresult comparing unit 330 could detect a column shift between the twostrings using the position information added to the image datarecognition result 315 and magnetic data recognition result 325. In thiscase the positions of the first (or last) characters in the image datarecognition result 315 and magnetic data recognition result 325 could becompared to determine if the character strings are offset from eachother.

If the two strings do not have the same number of characters, the columnshifting correction process could align the strings by shifting onerelative to the other by a distance equal to or less than the differencein the number of characters. If the difference in the length of the twostrings is one character, for example, the strings are shifted so thatthe first or last characters in the character string of the image datarecognition result 315 and the character string of the magnetic datarecognition result 325 are aligned. If the difference in the length ofthe two strings is two characters, the offset can be corrected byshifting the strings 0, 1, or 2 characters.

As a further alternative, the column offset can be corrected by usingthe position information in the image data recognition result 315 andmagnetic data recognition result 325 to align the columns that areapparently corresponding. If the positions of the first character (orlast character) in the image data recognition result 315 and magneticdata recognition result 325 are not the same, for example, the stringscan be shifted so these character positions match.

As a further alternative, if the position of each character in the imagedata recognition result 315 and magnetic data recognition result 325 isknown, the strings can be shifted so that the characters at the samecharacter positions match.

Further alternatively, one or a plurality of column offset correctionpatterns could be defined, and the columns could be shifted according toa specific correction pattern without analyzing how the characters areshifted. These column offset correction patterns could, for example,shift the strings a specific number of columns in a specific directionrelative to each other, or shift the strings so that the first or lastcharacters in the strings are aligned. The strings are them comparedafter the column alignment is corrected, and if the match rate betweencharacters at the same column positions is less than or equal to aspecified value, the column offset is corrected again using a differentcorrection pattern. This trial and error process can be repeated untilthe match ratio between the compared characters exceeds a specifiedlevel.

After the alignment of the character strings of the image datarecognition result 315 and magnetic data recognition result 325 iscorrected, the comparison process compares and determines whether thecharacter strings match. If there was no offset between the characterstrings, the characters are compared one by one starting from the firstcharacter in each string. Characters confirmed to be the same by thiscomparison are then used as the final recognition result. Charactersthat do not match might or might not be correct, and are thereforeflagged as unrecognizable by outputting a question mark “?” in thecorresponding column. The result of this comparison is output as thecombined recognition result 335. A question mark is therefore output atthe first and eighth characters in the example shown in FIG. 6 becausethe first and eighth columns do not match.

The recognized characters in the combined recognition result 335 arethus those characters that are recognized as the same characters in boththe image data and magnetic data; the reliability of the combinedrecognition result 335 is therefore extremely high. The characters atthe columns output as a question mark are characters that do not matchin the image data and magnetic data recognition results. Because therecognition result could be wrong if either the image data or magneticdata recognition result is used, this embodiment of the invention usesneither the image data recognition result nor the magnetic datarecognition result if the results are not the same. Recognition errorscan thus be eliminated with a very high degree of reliability.

While embodiments of the invention have been described and illustrated,further alternatives, modifications, variations and applications of theinvention will be apparent to those skilled in the art in light of theteachings herein. Thus, the invention disclosed herein is intended toembrace all such alternatives, modifications, variations andapplications as may fall within the spirit and scope of the appendedclaims.

1. A character recognition apparatus for recognizing a character stringcomposed of a plurality of characters printed with magnetic ink on aprint medium, the character recognition apparatus comprising: a magneticsensor for detecting magnetism from the character string printed inmagnetic ink and outputting magnetic data; an optical sensor foroptically reading the character string printed in magnetic ink andoutputting image data; magnetic recognition means for recognizingcharacters in the character string using the magnetic data output by themagnetic sensor, and outputting a magnetically-recognized characterstring; image recognition means for recognizing characters in thecharacter string using the image data output by the optical sensor, andoutputting an optically-recognized character string; column offsetdetection means for detecting a shift in column alignment of charactersin the magnetically-recognized character string with respect tocorresponding characters in the optically-recognized character string;column offset correction means for correcting the column offset andaligning corresponding characters of the magnetically-recognized andoptically-recognized character strings, if the column offset detectionmeans detects a shift in character column alignment; and comparisonmeans for comparing results at corresponding positions in themagnetically-recognized and optically-recognized character strings basedon the column alignment after column offset correction is performed bythe column offset correction means, and, for each position comparison,outputting (1) the common character if the magnetically-recognized andoptically-recognized character at that position match, or (2) a questionmark if the magnetically-recognized and optically-recognized characterat that position do not match or if one or both of themagnetically-recognized or optically-recognized character is missing. 2.A character recognition apparatus as described in claim 1, wherein thecolumn offset detection means determines that there is an offset in thecharacter column alignment when the number of characters in themagnetically-recognized character string and the number of characters inthe optically-recognized character string are not the same; and thecolumn offset correction means corrects the column offset by shiftingone of the magnetically-recognized character string or theoptically-recognized character string relative to the other by an amountequal to or less than the difference in the number of characters in thestrings.
 3. A character recognition apparatus as described in claim 1,wherein the magnetic sensor outputs magnetic position informationdenoting the position where magnetism of a particular character wasdetected, along with the magnetic data; the image recognition meansdetects the position of each character during character recognition, andoutputs image position information denoting the corresponding detectedpositions; and the column offset detection means detects the columnoffset by comparing the position of the first or last character of themagnetically-recognized character string based on the magnetic positioninformation and the corresponding position of the first or lastcharacter of the optically-recognized character string based on theimage position information.
 4. A character recognition apparatus asdescribed in claim 3, wherein the column offset correction means alignscorresponding columns in the character strings based on positioninformation contained in the magnetic position information for eachcharacter in the magnetically-recognized character string and positioninformation contained in the image position information for eachcharacter in the optically-recognized character string.
 5. A characterrecognition apparatus as described in claim 1, wherein the column offsetcorrection means shifts the correlation between themagnetically-recognized character string and the optically-recognizedcharacter string based on a first pattern selected from one or morepredefined offset patterns to correct the column alignment.
 6. Acharacter recognition apparatus as described in claim 5, wherein thecolumn offset correction means selects a second pattern to correct thecolumn offset, when the match rate of the character strings compared bythe comparison means based on the column alignment corrected accordingto the selected first pattern is less than or equal to a specified rate.7. A character recognition method for recognizing a character stringcomprising a plurality of characters printed with magnetic ink on aprint medium, the character recognition method comprising: implementingat least in part at least one of the following steps using one or moreprocessors: detecting magnetism from the character string printed inmagnetic ink and outputting magnetic data; optically reading thecharacter string printed in magnetic ink and outputting image data;recognizing characters in the character string using the outputtedmagnetic data, and outputting a magnetically-recognized characterstring; recognizing characters in the character string using theoutputted image data, and outputting an optically-recognized characterstring; detecting a shift in column alignment of the characters in themagnetically-recognized character string with respect to correspondingcharacters in the optically-recognized character string; correcting thecolumn offset and aligning corresponding character columns of themagnetically-recognized and optically-recognized character strings, if ashift in the character column alignment is detected; comparing resultsat corresponding positions in the magnetically-recognized and opticallyrecognized character strings based on the column alignment after columnoffset is corrected; and outputting, for each position comparison, (1)the common character if the magnetically-recognized andoptically-recognized character at that position match, or (2) a questionmark if the magnetically-recognized and optically-recognized characterat that position do not match or if one or both of themagnetically-recognized or optically-recognized character is missing. 8.A non-transitory tangible medium containing a set of instructions toperform the character recognition method of claim 7.